1-pulley systems will have an effect on slowing down ALL accessories, but within safe levels both on the street and track. It's also cheaper to make, since it shares the same pulley as the S85 M5.

The 2-pulley system on the Macht Schnell systems gives the benefit of added power (actually freed up power), without any sacrifice. There's a couple of reasons why this method is chosen:

- BMW A/C clutch systems are designed to fully disengage at WOT, there is no need to underdrive that part of the system. IMHO, E9X AC systems are already weak in stock form, no need to further cripple it.
- Macht Schnell replacement belts are standard off-the-shelf belts that can be purchased from any auto parts store if/when needed. If you've ever tried searching for a double-sided 6-rib belt at an auto parts store, you'll know what I mean.

The MS pulley systems are priced comparatively with most 1-pulley systems, and a large number of them are used on the track. It's simply the best bang for the buck.

That makes sense. Jus to clarify it doesn’t affect water pump or AC pump while running at higher RPM, IE track conditions, yet still delivers power? How? Is the MS pulley the same diameter but made with lighter material hence creating less parasitic drag?
Thanks

Hey guys, I have the Dinan Pulley and its great for mid range. No AC power loss, no over heating and you can feel the difference with it installed. I just bought it this year and am already selling it. It is for 2009 and after M's. Only reason I am selling it is because you can not have it installed with a super charger and I am super charging my car this month. (As dumb as it sounds I did not know this and wish I could keep it with a SC, that's how significant it was to me) let me know if any one is interested. Receipts to prove its new.

That makes sense. Jus to clarify it doesn’t affect water pump or AC pump while running at higher RPM, IE track conditions, yet still delivers power? How? Is the MS pulley the same diameter but made with lighter material hence creating less parasitic drag?
Thanks

Slightly lighter, as well as slightly spinning the accessories slower - freeing up power due to less parasitic drag.

Most crank pulleys on the market today are relatively similar sized, with exception of the Dinan unit.

Have the Dinan, very happy with it. Added benefit in addition to power: engine ran much smoother at start up and low RPMs. Only real downside is that oil/engine temp runs slightly hotter (maybe 5-10 deg judging by the needle) in high RPM driving in hills. AC being underdriven not noticeable. Also some dealers less likely to deny warranty claims with Dinan (local dealer confirmed this, even if they don't sell Dinan products).

Our kit is engineered using Aircraft Grade Billet 6061 Hard Coat Anodized Aluminum. After months of R&D in house and overseas (various climates & conditions) we concluded that there may be a slight power increase by going smaller than our pulley but the trade off is a chance of making the engine run hotter or possibly overheat (we noticed this in both DCT cars and Manual cars on and off the track), we choose reliability over that extra 1-2 rwhp that we may get from a smaller pulley. Testing in Miami, FL and in other hot climates was a must in our R&D process to take things to the “extreme limits”.

Another key element in the development of the Signature Pulley Kit was to retain the “Factory Crank hex Drive Adapter”, this was important to keep this factory feature for its inherent purpose. The pulley kit does not modify factory harmonics or dampening. Stronger side walls were the last key element in choosing our size over a smaller design.

So, the AA pulley and MC pulley do not increase engine temps because they are of normal size and do not slow down accesories? Im torn between MC and AA. im sure they are both great.... i dont want to over heat if i track but I want the benifit of the extra power....hmmm hard choice

No. They slow down accessories or they would not add any power. I think AA is saying its pulley does not slow down accessories like the water pump quite as much in order to maintain coolant flow and therefore does not make quite as much power.

No. They slow down accessories or they would not add any power. I think AA is saying its pulley does not slow down accessories like the water pump quite as much in order to maintain coolant flow and therefore does not make quite as much power.

I think the difference is negligible. Macht Schnell claims gains of 9-14hp and AA claims 12+ hp. Both claim factory harmonics stay in tact. Only differential I see would be price and AA has a $50 off sale right now.

Slightly lighter, as well as slightly spinning the accessories slower - freeing up power due to less parasitic drag.

Most crank pulleys on the market today are relatively similar sized, with exception of the Dinan unit.

This is why I bought my pulley and intake setup from EAS/Macht Schnell. Tom has done a lot of research on his products and it show in the final product. I have seen many other pulley kits and at the end of the day Macht Schnell seems to be the right fit for me

I think the difference is negligible. Macht Schnell claims gains of 9-14hp and AA claims 12+ hp. Both claim factory harmonics stay in tact. Only differential I see would be price and AA has a $50 off sale right now.

Also MC has 2 pulleys to install where AA has only 1. I have the AA and installed it myself in 45 minutes. I love this thing. Made the car a completely different animal

I think the difference is negligible. Macht Schnell claims gains of 9-14hp and AA claims 12+ hp. Both claim factory harmonics stay in tact. Only differential I see would be price and AA has a $50 off sale right now.

Major differentials are the AA is single pulley system and uses a proprietary belt. MS uses two pulleys (not affecting A/C operation, which would also spin slower during everyday driving) and normal off-the-shelf belts for when replacement time is neeed (normal maintenance).

So I went with the Active Autowerks Pulley and decided to install it myself. The install was relatively easy for someone who's never done engine work. I did have trouble getting the A/C belt back on, but my fiance helped out and we got it figured out.

First thing I noticed was that starting the car seemed much smoother/quicker. I took her out for a test run to make sure nothing would blow up and am impressed with the results. I would suggest this mod to anyone!

Has anyone noticed any decreased drivability with aftermarket pulleys installed? I always have the a/c going as it gets quite hot here in sofla. Will the car drive just as smoothly as stock with the ac going, radio on, etc?

Only time I ever changed the pulleys on one of my cars was yearsss ago on my Honda accord. I def noticed an increase in power but with the a/c on the car drove very erratically.

Quite the opposite actually (I have the Dinan). Low end/1st gear both cold and warm the car drives smoother. A/C, stereo, etc has no impact.

Quote:

Originally Posted by gatorfast

Has anyone noticed any decreased drivability with aftermarket pulleys installed? I always have the a/c going as it gets quite hot here in sofla. Will the car drive just as smoothly as stock with the ac going, radio on, etc?

Only time I ever changed the pulleys on one of my cars was yearsss ago on my Honda accord. I def noticed an increase in power but with the a/c on the car drove very erratically.

Has anyone noticed any decreased drivability with aftermarket pulleys installed? I always have the a/c going as it gets quite hot here in sofla. Will the car drive just as smoothly as stock with the ac going, radio on, etc?

Only time I ever changed the pulleys on one of my cars was yearsss ago on my Honda accord. I def noticed an increase in power but with the a/c on the car drove very erratically.